A bunch of new pages:

common/: dig, gzip, rm, sort, zfs, zpool
linux/: apt-get, shutdown
osx/: airport, caffeinate, diskutil, networksetup open, pgrep, qlmanage, say, shutdown, sysctl, system_profiler

Edits to existing pages:
curl: Added simple download example
find: Added iname and size exmaples
grep: Edited -c description
ps: Added wide lines example
ssh: edited -D description, added simple port forwarding example
unzip: added list option

linux/apt-get.md

@@ -0,0 +1,24 @@
+# apt-get
+
+> Debian and Ubuntu package management utility
+
+- Synchronize list of packages and versions available. This should be run first, before running subsequent apt-get commands.
+ 
+`apt-get update`
+
+- install a new package
+
+`apt-get install {{package}}`
+
+
+- remove a package
+ 
+`apt-get remove {{package}}`
+
+- Upgrade installed packages to newest available versions
+
+`apt-get upgrade`
+
+- Upgrade installed packages (like `apt-get upgrade`) including removing obsolete packages and installing additional packages to meet new package dependencies. 
+
+`apt-get dist-upgrade`

linux/shutdown.md

@@ -0,0 +1,16 @@
+# shutdown
+
+> Shutdown and reboot the system
+
+- Reboot or poweroff (halt) the system immediately
+
+`shutdown -r now`
+`shutdown -h now`
+
+- Reboot in 5 minutes.
+
+`shutodwn -r +5 &`
+
+- Cancel a pending shutdown/reboot operation
+
+`shutdown -c`